The Fascinating World
of Biominerals
George R. Rossman
Division of Geological and Planetary Sciences
California Institute of Technology
Pasadena, CA
Fossil Biominerals
Fossil mineralized hard parts of
organisms are first preserved
from multicellular life forms that
lived about 540 million years
ago.
Multicellular life itself evolved
more than 3000 million years
ago.
Miocene Foram
test
Apatite Group
Apatite: Ca5(PO4)3(OH)
Fluorapatite: Ca5(PO4)3F
Carbonate apatite Ca5(PO4,CO3)3(OH,O)
Durango, Mexico
Calcium Carbonate Phases
Formula
Structure
Calcite
CaCO3
Trigonal
Aragonite
CaCO3
Orthorhombic High Mg/Ca ratio
Vaterite
CaCO3
Hexagonal
higher T
Monohydrocalcite
CaCO3·H2O
Hexagonal
low T
Ikaite
CaCO3·6H2
O
Monoclinic
forms near 0°C
Carnegie Museum
Phase
Comments
Pseudomorph of
calcite after ikaite,
Russia.
On display at the
Carnegie museum,
Pittsburgh.
Calcium Carbonate Biominerals
Organisms use calcite, aragonite, vaterite, monohydrocalcite and
amorphous hydrous calcium carbonate.
In the Kingdom Monera (archaebacteria, blue-green algae) calcite,
aragonite and monohydrocalcite are used.
In the Kingdom Protoctista (sea-weeds,
slime molds) calcite, aragonite, vaterite
and amorphous calcium carbonate is used.
In the Animal Kingdom, all four are used.
In the Plant Kingdom, calcite, aragonite and vaterite are used.
Brittle
Star’s
calcite
optics
Alzenberg et al. (2001)
Brittle stars have the
ability to rapidly
change color.
Each calcite lens
directs light to a
nerve fiber.
www.ucmp.berkeley.edu/collections/invert.html
from Clarkson 1975
Paleoplace.com
Tribolite’s Calcite Eyes
Aragonite
Sr, Mg, and organics in water can
favor aragonite formation.
Black Bearpaw Shales, Alberta
Erzberg, Striermark, Austria
Aragon, Spain
Vaterite, CaCO3
Microbial biscuits in Lake Issyk-Kul, Kyrgyzstan.
A layer that often occurs on (parts of) cormorant’s eggs.
Sagittal otoliths with vaterite replacement in lake trout in the Great Lakes.
Spicules of topical ascidians (sea squirts).
Parmentier J & van
Egmond W (1998)
http://micscape.simpl
enet.com/mag/artaug
98/tuni2.html
Vaterite
spicules
Vaterite cluster
Spangler, G (1995)
http://www.fw. umn.
edu/biochr/
GRS_home/FRD_
page/FRD.html
Aragonite otoliths
Scott C: www.keele.ac.uk/depts/ch/groups/csg/cas/
Pomacea paludosa (Apple Snail)
Aragonite shell
Vaterite egg capsules
Pomacea paludosa - Lake Oklawaha, FL
Amorphous CaCO3
in the foot.
Monohydrocalcite
Crusts on the walls of caves where cold, Mg-rich waters drip.
Lake Issyk-kul, Kyrgyzstan; A saline lake.
A precipitation from halophilic strains
of Bacillus that live in saline soil.
A guinea pig bladder stone.
Lake Issyk-Kul’ and Tien Shan,
Kyrgyzstan
http://earth.jsc.nasa.gov/
Ikaite
Ikaite, CaCO3 · 6H2O, was discovered in Greenland in a fjord at
the site of a carbonate-rich near-freezing water seepage where it
forms tall underwater columns.
When it warms to room temperature, it decomposes into a mush
of water and anhydrous CaCO3 .
Images from: Seaman P and Buchardt B (1998)
http://www.geocities.com/RainForest/Vines/1486/
Amorphous silica is used by a wide variety of
organisms.
These include foraminifera, radiolarians,
heliozoata, bachillariophyta, sponges,
annelids, molluscs, arthropods,
echinoderms and plants
Foram test
Radiolarian
Sponge spicule
@ University of Sydney
Silica
Bamboo
Silica
A silica residue is left
when the organic
matter in a bamboo leaf
is dissolved in sodium
hypochlorite (bleach).
Bamboo Silica
Bamboo Silica
Bamboo silica
“Bamboo contains
silica (sand)
and dulls blades
quickly.”
Silica structures in a sponge
Iron oxides
Magnetite
Fe3O4
x
Maghemite
g-Fe2O3
?
Goethite
a-FeO(OH)
Lepidocrocite
g-FeO(OH)
‘Ferrihydrite’
Amorphous hydrous iron oxides
x
x x
x
x
x
x
x
x
x
x
x
x
x
Nip Island, Palau
Chitons (cl. Polyplacophora) eating rock)
Eating Rock
Scrape Marks in the carbonate
Chitons
library.thinkquest.org/J001418/chiton.html
www.vattenkikaren.gu.se/fakta/arter/mollusca/prosobra/helc
pell/helcpee.html
http://edweb.sdsu.edu/triton/tidepoolunit/Graphics/jpgs/OwlLimp.jpg
Chiton Radula
Chiton Teeth
Chiton’s and snail’s teeth
Magnetite
Lepidocrocite
Amorphous
Some
molluscs
use
amorphous
silica
Snail radula (Genus Katharina)
Magnetite crystals
produced by
magnetotactic
bacteria
Goethite sheaths around Leptothrix bacteria
The sheathed bacteria are common in aquatic habitats
www.bsi.vt.edu/chagedor/biol_4684/Microbes/Leptothrix.html
Bacterially precipitated MnO2
Manganese oxide
precipitates around
spores of the
marine bacillus,
SG-1, isolated
from sediments off
Southern
California.
It is a sheet oxide,
probably birnessite
Polymorphs of MnO2
Pyrolusite
Ramsdellite
Hollandite
Romanechite
Todorokite
Birnessite
1x1
1x2
2x2
3x2
3x3
sheet
Iron Sulfides
Pyrite is used by Monera (archaebacteria, blue-green algae)
Fluorite mysid statolith
Opossum Shrimps
www.museum.vic.gov.au/crust/mysidgal.html
Statoliths are small grains
that help the animal keep
orientation.
Molpadia
A holothurian
(sea cucumber)
Holothurians are
echinoderms that have a
calcareous exoskeleton. It
has a leathery consistency.
The exoskeleton of
Molpadia contains
biominerals.
Molpadia calcium phosphate skin granules
Sea cucumber
These granules are rigorously
X-ray amorphous. When
heated, they show lines from
hematite and carbonate apatite,
Ca5(PO4,CO3)3(OH,O).
Molpadia calcium iron phosphate skin granule
Molpadia
calcite spicule
These are found in
early postlarval
individuals.
They are replaced
by the amorphous
calcium-iron
phosphate in the
adult stage.
Molpadia intermedia
Juvenile
Molpadia calcite
anchor spicule
Ascidians
The ascidians are are a class of tunicates.
They are also called sea squirts.
Tunicates have a tunic that protects
them from predators.
Their tunics contain biominerals.
Ascidian species collected in
the vicinity of Asamushi
Marine Biological Station.
Aragonite spicules from an ascidian
Halocynthia roretzi
is a popular sea food
in Japan
home.hiroshima-u.ac.jp/akirahs/eng/ascidian.html
Herdmania (ascidian) vaterite
Culeolus
(ascidian)
amorphous
CaPO4
Sulphates:
Celestite, SrSO4
Barite, BaSO4
Gypsum, CaSO4
Celestite is used by marine protoctists (algae &
diatoms) to form skeletons.
Because sea water is undersaturated in SrSO4, it
dissolves rapidly when the organism dies.
Gypsum is used by Coelenterata
Barite is used by Rhizopodea (protozoans) and
Charophyta (green algae)
Nontronite
Na0.3 Fe23+ (Si,Al)4 O10 (OH)2 · nH2O
A low aluminum, nearly monomineralic greenish
nontronite with a sheath morphology is found in the
vicinity of white smokers. Fe-oxidizing bacteria play a
role in its formation.
Kohler B, Singer A, Stoffers P (1994) Biogenic nontronite from marine white smoker chimneys. Clays & Clay
Minerals 42:689-701
White smoker is the name for chimneys made out of iron, sulfur,
lead, and zinc sulfide minerals that have high temperature (250300°C) plumes of white "smoke" coming out of them. Much of the
white smoke is caused by crystallization of very fine-grained
minerals made out of anhydrite (CaSO4).
Bruce Strickrott, DSV Alvin Pilot. www.lostcity.washington.edu
www.ocean.udel.edu/deepsea/
Human Biomineralogy
Structural components:
Teeth, Bones:
apatite group minerals
Pathology:
oxalates, phosphates
carbonates
Sensorary:
Fe-oxide?
Calcium oxalate dihydrate (weddellite)
These crystals of CaC2O4 · 2H2O were
recovered from a human thyroid gland
Calcium oxalate monohydrate
CaC2O4 · H2O
These crystals
formed in the
myocardium of an
48-year old
alcoholic woman.
(whewellite)
Kidney Stones
Other biominerals:
Struvite
Whitlockite
Brushite
Carbonate-apatite
Newberyite
Calcite
Weddellite
Calcium oxalate monohydrate
(whewellite)
www.herringlab.com
Summary
In 1962, Caltech paleoecologist Heinz Lowenstam
discovered that organisms produce iron minerals.
Today, biomineralogy is a rapidly growing field.
More than 60 different inorganic crystals are
recognized as products of life.
Three billion years of microbial action led to the
accumulation of many valuable ore deposits.